Apparatus for winding a plurality of linear materials

ABSTRACT

In a system for twisting together several ends of heavy treated glass yarns from separate supply packages, an improved means for detecting interruption in the supply of an individual end which employs individual tachometer generators associated with and driven by each supply package. Each tachometer generator produces an electrical signal whose strength is proportional to the rotational speed of its associated package. A detector circuit senses when any one such signal falls below a predetermined minimum, and triggers an interruption of the electrical power supply to the strand feeding and twisting apparatus to shut down the entire system.

[ Dec. 24, 1974 APPARATUS FOR WINDING A PLURALITY 0F LINEAR MATERIALS 21 Appl [58] Field Inventor:

Assignee:

Filed:

Raymond E. Hurley, Heath, Ohio Owens-Corning Fiberglas Corporation, Toledo, Ohio Jan. 26, 1973 Int. Cl DOlh 1/28 of Search 242/36, 37 R, 38; 324/161, 324/177; 57/81, 83, 90

References Cited UNITED STATES PATENTS Beers 242/36 Goodhue et a1. 57/81 X Primary Examiner.lohn W. Huckert Assistant Examiner-Charles Gorenstein Attorney, Agent, or Firm-Carl G. Staelin; John W. Overman; Richard D. Grauer [57] ABSTRACT In a system for twisting together several ends of heavy treated glass yarns from separate supply packages, an improved means for detecting interruption in the supply of an individual end which employs individual tachometer generators associated with and driven by each supply package. Each tachometer generator produces an electrical signal whose strength is proportional to the rotational speed of its associated package. A detector circuit senses when any one such signal falls below a predetermined minimum, and triggers an interruption of the electrical power supply to the strand feeding and twisting apparatus to shut down the entire system.

2 Claims, 4 Drawing Figures PATENTEBUEBZMQH 3,855,774

SHEET 2 0F 2 30 THRESHOLD DETECTORS. MOTOR. m

/I8 m 0 ID SSTAIITE MAGNETIC TENSION SWITCH. CLUTCH SENSOR. re.

re TIME ELECTRIC DELAY BRAKE TACH GENERATOVRS. 70

POWER 7 SUPPLY.

APPARATUS FOR WINDING A PLURALITY OF LINEAR MATERIALS BACKGROUND OF INVENTION This invention involves an improved system for feeding multiple ends of heavy treated glass yarns into a conventional twister winder. The invention has been employed in conjunction with the Whirlwind Twister Winder M-3750, manufactured by Warner & Swasey of Cleveland, Ohio. In this conventional twister winder, the individual ends or strands are fed into the winder from supply packages held in a creel. The strands are twisted in the horizontal twister winder unit and collected on a take-up package.

During operation, interruptions in the supply of individual strands occur periodically, either because of a break in the strand between the supply package and the twister winder or because the supply of strand on an in dividual supply package has become exhausted. It is, of course, essential that the twisting and winding operation be shut down immediately upon such an interruption in the supply of any single strand. Since the linear rate of strand feed may be as high as 450 feet per minute, it becomes essential to provide reliable means for immediately detecting the occurrence of an interruption.

One method employed by the prior art is the socalled drop wire detector, wherein each horizontally moving strand passes through a central hole in a thin light weight electrically conductive metal plate. The plate is held in a frame so that it can only move vertically. The plate thus hangs from the horizontal longitudinally moving strand. The tension in the strand is sufficient to overcome the weight of the plate, so that the strand is not significantly deflected downwardly thereby. When a break occurs in the strand, the supporting tension in the strand is lost and the plate falls to interruupt the main power supply. Thus, the plate acts as the movable element of the short circuiting switch.

The drop wire break detector, however, is not effective in applications where heavy treated glass yarns or strands are being twisted. An example of such application is in rubbercoated yarns used for gear belts having high tensile strength and resistance to stretch. The increased weight and stiffness of such strands would require a far heavier dropwire plate, whose weight would undesirably increase the drag on the linearly moving strand and would also tend to abrade the coating from the strand.

Accordingly, it is the primary object of the present invention to provide an improved means for detecting an interruption in the supply of an individual strand to a strand twisting and winding operation, which detector is particularly suitable for use with heavy strand material.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of the winding system of the present invention, with portions of the system being shown in simplified schematic form.

FIG. 2 is a schematic block diagram of the controls for the system of FIG. 1.

FIG. 3 is an electrical circuit diagram of the strand interruption detector circuit.

FIG. 4 is the side elevation of the strand feeding portion of the system of FIG. 1.

DETAILED DESCRIPTION OF THE DISCLOSURE Referring to FIG. 1 in particular, the system generally comprises a twister winder l0, creel frame 12, feed mechanism 14, a drive 16 for the feed mechanism and a tension sensor 18.

Creel frame 12, shown schematically, provides a rotatable mounting for a series of supply packages 20, each of which contains a winding of an individual strand or yarn or end 22. The individual strands travel back and forth horizontally between a series of guides prior to advancing toward feed mechanism 14. This lacing arrangement provides sufficient strand length to keep exposed any breaks which may occur upon shut down of the apparatus, that is, the broken end will not advance into an inaccessible portion of the twisterwinder. Such a lacing arrangement is conventional and is therefore shown only schematically.

After the strands pass through feed mechanism 14 and tension sensor 18, they are routed through a strand separator 24 immediately prior to entry into the hollow tube portion 26 of the twister. The separator is conventional, and serves to keep the strands from becoming prematurely twisted or snarled.

Strands 22 exit from tube 26 through hole 28 and then pass over balloon shape control unit and flyer disk 30. Tube 26 and flyer disk 30 are driven by drive motor 32 and drive belt 34. As described above, the twisterwinder 10 is of conventional design.

Twisted strands 36 enter the balloon zone after leaving flyer disk 30, and are then collected at apex guide 38. The strands are then routed through a conventional tension compensating system, shown only schematically, and from there to a reciprocating traverse arm 40 which feeds the twisted strand onto take-up package 42. The feed mechanism 14 for pulling strands 22 off of supply packages 20 and supplying them to the twister winder unit 10 receives its power indirectly from drive motor 32. A power take-off belt 44 drives input shaft 46 off of the rotating hollow tube 26, shaft 46 serving as the input shaft to a conventional variable speed transmission 48. Output shaft 50 from transmission 48 is connected to a magnetic clutch 52, which in turn drives a first drive roller 54 of feed mechanism 14 through belt 56.

As best shown in FIGS. 1 and 4, feed mechanism 14 includes three identical drive rollers 54, 58 and 60, which have their axes arranged parallel and coplanar, and which are positively interconnected for simultaneous rotation at identical speeds by belts 62 and 64. A further belt 66 driven off roller 58 is connected to coaxially mounted electric brake 68 and flywheel 70.

The feed mechanism drive rollers are mounted within a housing 72, which also contains two idler rollers 74 mounted in the upper lid portion 76 of the housing. The journals 78 for the idler rollers are biased downwardly from lid 76 by springs 80, which serve to continuously bias idlers 74 downwardly into contact with the drive rollers, as shown in FIG. 4.

Referring now to FIG. 3, there is shown a circuit for detecting when the supply to the feed mechanism 14 of any one or more of the individual strands 22 has ceased. Such an interruption may occur when the supply on a package has been fully consumed or when an individual strand has broken. Each supply package 20 has a tachometer generator associated with it, so that rotation of the package as the strand is pulled off it by the feed apparatus causes rotation of the associated tachometer generator at the same or a proportional speed. A belt drive, for example, may interconnect each package with its associated tach generator. Driving the tach generator directly off the supply packages, rather than off the linearly moving strands at a downstream location, assures immediate response to an interruption in strand supply, whatever the cause. Each of the individual tach generators T.G.,, T.G. etc., is connected to an associated threshold detector circuit 82, 84, 86, etc., respectively, which are identical. Only detector circuit 82 will be described in detail, and it is to be understood that the remaining detector circuits 84, 86, etc., are identical. The number of tach generators and associated detector circuits are, of course, identical to the number of supply packages. Typically, three to six supply packages may be involved in a twisting operation.

The tach generator T.G. provides a voltage proportional to the speed at which it is turning. This voltage appears between a positive terminal 88 and a negative terminal 90. The positive terminal 88 is connected to one end of a resistor 92, the other end of which is connected to the base 94 of a PNP transistor 96. The transistor 96 also has a collector 98 and an emitter 100. The emitter 100 is connected to a point of positive voltage V,, which may be, for example, 5 volts DC. The emitter 100 is also connected to one end of a resistor 102, the other end of which is connected to the base 94. The negative terminal 90 of tach generator T.G. is connected to the junction of the resistor 102 and the point of voltage V The base 94 of transistor 96 is further connected through a resistor 104 to the terminal 106 of a switch 108. A switching arm 110 of the switch 108 is connected to ground. Switch 108 is provided to allow any individual tach generator and associated detector circuit to be disconnected in the event it and its associated supply package are not being used. The values of resistors 92, 102 and 104 are selected so that, with switch 108 closed, that is, with switching arm 110 in electrical contact with terminal 106, the voltage applied between the base 94 and emitter 100 of transistor 96 will be less than the voltage necessary to render transistor 96 conductive, for example, 0.6 volts, as long as the voltage between positive terminal 88 and negative terminal 90 of tach generator T.G., is greater than a predetermined minimum voltage, for example, 2 volts.

The collector 98 of the transistor 96 is connected to the base 112 of an NPN power transistor 114. In a similar manner, the collectors of the transistors corresponding to transistor 96 in each of the remaining respective detector circuits 84, 86, etc., are connected to the base 112 of transistor 114. The collector 116 of transistor 114 is connected to the positive terminal 118 of a power supply 120 and the emitter 122 of transistor 114 is connected to the negative terminal 54 of the power supply 120. Power supply 120 may be any known type of DC. power source, such as a full wave rectifier, a four diode bridge, and so forth. The power supply 120 applies voltage to drive motor 32 and clutch 52 to operate feed mechanism 14 and twister winder 10. If the voltage between positive terminal 118 and negative terminal 124 should drop to zero volts, such units will shut down.

The operation of the circuit of FIG. 3 will now be described. lf switch 108 is open, that is, if there is no contact between switching arm 110 and terminal 106, detector circuit 82 will be disconnected from ground voltage and there will be no path for current created by voltage V to flow. In this case, the base 94 and emitter 100 of transistor 96 will be at approximately the same voltage and transistor 96 will be nonconductive. Hence, no current will flow from the collector 98 to the base 112 of the transistor 114 and the transistor 114 will be nonconductive. It should be noted that with the switch 108 open, the voltage provided by tach generator T.G. if any, is immaterial to the operation of detector circuit 82.

With the switch 108 closed, the transistor 96 can become conductive if the voltage provided by tach generator T.G. falls below the predetermined minimum voltage. As long as tach generator T.G. is running, the positive voltage at the positive terminal 88 maintains the base 94 of transistor 96 at the same voltage as the emitter 100. In this case, transistor 96 remains nonconductive and no collector current therefrom can flow to the base 112 of transistor 114. Thus, transistor 114 remains nonconductive. It should be noted that the speed of the tach generator T.G. will vary depending upon the diameter of the package as the strand is consumed. In one specific embodiment, the voltage output during normal operation varies between 2 and 14 volts. It does not matter at what speed the tach generator runs so long as it runs fast enough to provide the predetermined minimum voltage.

When the speed of tach generator T.G. falls below a selected minimum speed, due to a break in the individual strand or exhaustion of the strand supply on a particular package, the voltage between positive terminal 88 and negative terminal 90 falls below the predetermined minimum voltage. Now, the voltage at the base 94 of the transistor 96 falls more than 0.6 volts below the voltage at the emitter 100 and the transistor 96 begins conducting. This allows current to flow from the point of voltage V,, through the emitter-collector junction of the transistor 96 to the base 112 of the transistor 114. This current renders the transistor 114 conductive. As the tach generator T.G. comes to a complete stop, the transistor 96 become more conductive and more current flows into the base 112 of the transistor 114, until eventually the transistor 114 is in saturation.

With the transistor 114 in saturation, a short circuit appears across the positive terminal 118 and the negative terminal 124 of power supply 120. This causes the voltage provided to drive motor 32 and clutch 52 to become zero, and hence, twister-winder 10 and the feed drive 14 shut down immediately.

In practice, it takes the twister-winder 10 about two and one-half seconds to come to a complete stop. Since clutch 52 disengages immediately upon interruption of power, the feed drive 14 would also stop immediately due to the high drag created by the heavy strand materials. The two and one-half seconds of continued running of the twister would therefore tend to pull the strands tight onto disk 30, with resulting severe abrasion of the strand coatings. To eliminate this problem, flywheel 70 is provided to create sufficient angular momentum to maintain continued rotation of drive rollers 54, 58 and 60. After about a 2 second delay, as controlled by a conventional time delay unit schematically shown in FIG. 2, electric brake 70 is actuated to positively stop the drive rollers of feed mechanism 14.

The provision of the flywheel not only avoids abrasion of the strands against disk 30, but also provides some looseness in the system which facilitates rethreading of the strands during shutdown.

In one specific embodiment of the circuit, the following component values were used:

Resistor 92 820 ohms Resistor 102 22,000 ohms Resistor 104 1,800 ohms Transistor 96 2N5 l 34 Transistor 114 2N492l This invention may be further developed within the following claims. Accordingly, the above specification is to be interpreted as illustrative of only a single operative embodiment of this invention, rather than in a strictly limited sense.

1 now claim:

1. In strand winding apparatus having a plurality of individual strand supply packages rotatably mounted on a creel for supplying the strands to be wound, said creel having a long path through which the strands are threaded to accumulate a substantial length of each strand between its package and the exit point from said creel, and electrically driven strand feeding means and twisting means, the improvement comprising:

a flywheel for maintaining the speed of said strand feeding means substantially constant; a brake connected to said flywheel; a time delay circuit connected to said brake; tachometer generator means operatively connected to at least one supply package to be driven thereby, said tachometer generator means operative to generate an electrical signal whose magnitude is proportional to the rotational speed of its assoticated supply package; detector circuit responsive to a biasing signal and to the signal from said tachometer generatoe means for closing an electronic switch when the magnitude of at least one tachometer generator signal drops below a redetermined minimum; and power interruption means responsive to the closing of said electronic switch for stopping said strand twisting means and for actuating said time delay circuit; said time delay circuit for actuating said brake to stop said flywheel and said strand feeding means after said twister means has stopped. 2. The invention as defined in claim 1, wherein the magnitude of the electrical signal is proportional solely to the rotational speed of its associated supply package. 1 

1. In strand winding apparatus having a plurality of individual strand supply packages rotataBly mounted on a creel for supplying the strands to be wound, said creel having a long path through which the strands are threaded to accumulate a substantial length of each strand between its package and the exit point from said creel, and electrically driven strand feeding means and twisting means, the improvement comprising: a flywheel for maintaining the speed of said strand feeding means substantially constant; a brake connected to said flywheel; a time delay circuit connected to said brake; tachometer generator means operatively connected to at least one supply package to be driven thereby, said tachometer generator means operative to generate an electrical signal whose magnitude is proportional to the rotational speed of its assoticated supply package; a detector circuit responsive to a biasing signal and to the signal from said tachometer generatoe means for closing an electronic switch when the magnitude of at least one tachometer generator signal drops below a redetermined minimum; and power interruption means responsive to the closing of said electronic switch for stopping said strand twisting means and for actuating said time delay circuit; said time delay circuit for actuating said brake to stop said flywheel and said strand feeding means after said twister means has stopped.
 2. The invention as defined in claim 1, wherein the magnitude of the electrical signal is proportional solely to the rotational speed of its associated supply package. 